A laminated reflective film means a film which can reflect and absorb light having a predetermined wavelength, and usually has a structure in which reflective layers are laminated on a substrate.
As the laminated reflective film, for example, JP 2009-86659 A describes an invention relating to a heat ray shielding film which transmits visible rays and selectively reflects near-infrared rays, and a laminated body including the same. In this case, the heat ray shielding film described in JP 2009-86659 A is characterized in including a high refractive index layer having a minimum transmittance (TMIN) of 90% or less in a wavelength region of 750 nm or more and 1300 nm or less and including a resin layer containing inorganic particles having a refractive index of 1.75 or more.
The high refractive index layer included in the heat ray reflective film in JP 2009-86659 A includes inorganic particles in a resin for the high refractive index layer while the inorganic particles are dispersed. The heat ray reflective film thereby obtains a desired refractive index. In this case, JP 2009-86659 A describes that a specific wavelength is selectively reflected preferably by a laminated film in which a high refractive index layer and a low refractive index layer having controlled optical film thicknesses are laminated alternately.
In addition, JP 2009-86659 A describes that a refractive index layer such as a high refractive index layer is formed by a so-called wet film forming method from a viewpoint of manufacturing cost or the like. In the wet film forming method, a coating solution including inorganic particles, a water-soluble polymer, and a solvent is coated on a substrate, dried, and the like.